A method and an arrangement for controlling an actuator unit of a drive unit is disclosed, for example, in U.S. Pat. No. 4,441,471. The actuator unit described in this patent defines a bypass position element for controlling the idle speed and is adjusted in the context of an idle rpm control when the throttle flap is closed. Outside of this operating state, the actuator unit is driven with at least one pregiven drive signal whereby it assumes a specific position. When the accelerator pedal is actuated and the throttle flap is opened, a movement out of the idle state takes place and the actuator unit is driven into a pregiven position. In the region of smaller throttle flap openings (for example, when parking), an unfavorable course of the rpm can occur when switching in higher loads such as power steering or climate control because of the nonactive idle control and the fixed position of the actuator unit and the small opening of the throttle flap. In extreme cases, this can lead to stalling of the engine. Stalling of the engine is especially the case in systems wherein a throttle flap actuator is used for idle control. In such systems, the idle rpm control is undertaken directly via the throttle flap in that a drive of a displaceable stop of the throttle flap is correspondingly actuated. This drive is lead to a specific position when there is a movement out of the idle range, that is, when the throttle flap is lifted from the stop. If this position is less than the idle position, then this can lead to a stalling of the drive unit when switching in higher loads during parking.